Varicellais the virus that causes chicken pox. This virus is transmitted through the air and from droplets of an infected person, and is considered highly contagious. Once a person has been infected, the virus lives within him forever, in the nerve ganglia of the spine. If ever the immune system falters, the virus can be reactivated in the form of shingles. The rash of shingles sheds the virus and can cause chicken pox in people who have never been immunized nor had the infection previously. Varicella is usually a mild disease for children, lasting about a week causing a characteristic itching rash in different stages of healing. The symptoms can be more severe in adults, stemming from secondary bacterial infections. The virus is present throughout the entire world.
In 1995, the U.S. approved a varicella vaccination for children 1-12years. The vaccine is considered 90% effective, and the chicken pox illness is not nearly as common as it was previously. The vaccination is highly recommended for people traveling to foreign countries who have never had the illness and never been vaccinated in the past. This is a two series vaccination, given 4-8weeks apart.
This vaccination is a live virus, so certain people are not eligible to take this immunization. Persons who are pregnant, have certain cancers, HIV/AIDS, or are allergic to gelatin or neomycin should NOT receive this vaccination. Adverse reactions include pain at the injection site, fever and/or rash. This vaccination causes a latent infection in the body, similar to how chicken pox illness does; therefore, people receiving this vaccine have shingles later in life.